1. Field of the Invention
Generally, the present relates to devices for use in improving blood circulation. More specifically, the present invention relates to a portable external counter pulsation device.
2. Description of the Related Art
Clinical external counter pulsation therapy (ECP) was developed to improve a human cardiovascular system (under operational control of a health care professional). The clinical ECP system is very large, not very portable and is also prohibitively expensive for home use, with systems retailing for thousands of dollars. Even if such a system were affordable, its sheer size makes usage in a home environment very difficult.
External counter pulsation (ECP) has been introduced during the last 3 decades as a non-invasive alternative approach to active physical exercise in patients suffering from severe coronary artery disease (CAD). Several prospective clinical trials have demonstrated a clear therapeutic benefit including improvement of clinical status and exercise performance as well as an improved quality of life. During ECP the aortic and intracoronary average and diastolic blood flow and pressure are increased while systolic pressure is decreased. This increase in blood flow results in increased shear stress in the arterial system suggesting also an improvement of the shear stress in the coronary artery bed. The mechanism by which ECP alleviates angina includes improvement of peripheral and coronary endothelial function, improvement of ventricular function, favorable peripheral effects similar to that of physical training and the recruitment and proliferation of collateral arteries. The latter process, termed arteriogenesis, may be initially triggered by physical forces: in the presence of a stenosis blood flow and consequently endothelial shear stress are increased across the lumina of pre-existing anastomotic arteries. Shear stress is a major trigger of arteriogenesis. Clinical studies have demonstrated a clear positive correlation between collateral formation and physical activity. A well-developed coronary collateral system minimizes the loss of myocardium in case of myocardial infarction and reduces the long-term cardiac mortality. However, only one third of the patients with CAD and residual stenosis or occlusions possess adequate collateral networks. ECP is therefore an attractive therapeutic option for the non-invasive stimulation of collateral growth.
In clinical ECP therapy programs, a patient must undergo the therapy for 35 one-hour sessions, usually scheduled over a 5-day work week for a period of seven weeks. This regimen can be rigorous and places demands upon a patient's schedule. If a patient misses sessions, it can have an adverse effect on the treatment.
The only ECP systems currently available are of the clinical type and some have received FDA approval. These systems, while touting their portability, remain bulky and in practical operation are not very mobile. The systems generally include a custom reclining bed and a control cart, which includes a display, input device, as well as the air and vacuum supply components. A number of air bladders (or cuffs) are provided for the patient to wear while reclining on the bed for treatment. These bladders are connected to the control cart with a series of hoses and sensor wires which monitor the patient's heartbeat as well as the performance of the air bladders.
There is therefore a need for a portable oscillating compression system that provides similar treatment to an ECP system at level suitable for unsupervised use that allows for more flexible treatment options, can be used to treat or improve a variety of patients, and can provide users with a measure of improvement in their cardiovascular system to relieve pain, improve circulation and quality of life.